Hadith 33

Sahih Bukhari

Book 30: Fasting

Chapter 21

If the intention of Saum was made in the daytime.

باب إِذَا نَوَى بِالنَّهَارِ صَوْمًا

Umm Ad-Darda’ said: Abu Ad-Darda’ used to ask, “Do you have food?” If we answered in the negative, he would say, “Then I am observing Saum (fasting) today.” Abu Talha, Abu Hurairah, Ibn ‘Abbas and Hudhaifa رضي الله عنهم did the same.
وَقَالَتْ أُمُّ الدَّرْدَاءِ كَانَ أَبُو الدَّرْدَاءِ يَقُولُ عِنْدَكُمْ طَعَامٌ فَإِنْ قُلْنَا لاَ. قَالَ فَإِنِّي صَائِمٌ يَوْمِي هَذَا. وَفَعَلَهُ أَبُو طَلْحَةَ وَأَبُو هُرَيْرَةَ وَابْنُ عَبَّاسٍ وَحُذَيْفَةُ رَضِيَ اللَّهُ عَنْهُمْ.
Sahih al-Bukhari 1924
حَدَّثَنَا أَبُو عَاصِمٍ، عَنْ يَزِيدَ بْنِ أَبِي عُبَيْدٍ، عَنْ سَلَمَةَ بْنِ الأَكْوَعِ ـ رضى الله عنه ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم بَعَثَ رَجُلاً يُنَادِي فِي النَّاسِ، يَوْمَ عَاشُورَاءَ ‏ ‏‏.‏
"‏ أَنْ مَنْ أَكَلَ فَلْيُتِمَّ أَوْ فَلْيَصُمْ، وَمَنْ لَمْ يَأْكُلْ فَلاَ يَأْكُلْ ‏"
Salama bin Al-Akwa`:

Once the Prophet (ﷺ) ordered a person on 'Ashura' (the tenth of Muharram) to announce, "Whoever has eaten, should not eat any more, but fast, and who has not eaten should not eat, but complete his fast (till the end of the day).